The present invention generally relates to a system and a method for generating hydroelectric power. More particularly, it relates to a system and a method of lifting water from a water source from a relatively lower position to a relatively raise position utilizing siphonic action and channeling the water from the relatively raised position down to a turbine driven generator.
Increases in population and technological advancements have created an unprecedented demand for new sources of energy. The use of traditional sources of energy such as coal and oil are resulting in the gradual depletion of natural resources as well as the release of harmful pollutants into the environment. The use of nuclear energy carries multiple risks including those associated with the disposal of nuclear waste byproducts. Alternative sources such as solar power and wind power have not proven to be reliable sources of energy.
Hydroelectric energy is a safer and a more cost effective form of energy. Hydroelectric power generally involves the use of falling water to drive turbines which in turn drive generators to generate electricity. While conventional hydroelectric power generation has typically depended on the availability of running water, many prior art systems have attempted to employ static water as a source to generate hydroelectric power.
One such prior art system, is disclosed in UK Patent Application GB 2 238 832 A. The prior art system disclosed raises water via a plurality of tanks and channels the water down to drive a generator. Each of the water tanks is positioned in increasingly elevated positions on individual base stands. A pipe extends from a box structure submerged below a water source to the first water tank. The pipe includes a descending portion below the water surface and a water lifting portion which rises steeply from below the water source up into the first water tank. A branch pipe extends from the descending portion of the pipe. An air compressor is connected to the free end of the branch pipe. The air compressor is used to initialize the flow velocity of the water through the pipe. In addition, if the flow of water through the pipe slows down, the air compressor is operated to increase the flow velocity of the water to the desired velocity. Similar pipes are provided between the other water tanks to successively raise the water from tank to tank. Each of these pipes includes a descending portion extending from the source water tank and a water lifting portion for lifting the water into the next higher water tank. Air compressors are connected to the branch portions of the pipes and operated to initialize the flow velocity of water through the pipes. The air compressors are then operated on a periodic basis to maintain the flow velocity of the water through the pipes. The water collected in the highest water tank is channeled down to a power generator turbine. A pump can also be provided in each pipe for accelerating the flow of water through the water lifting portion of the pipes.
Another prior art system, disclosed in U.S. Pat. No. 2,855,860, consists generally of a number of cascaded water tanks and a plurality of siphon pipes. Each siphon pipe generally consists of an inlet tube, a horizontal pipe section and a lower leg pipe section. The inlet tube of the first siphon pipe has a lower end submerged in a fluid source and an upper end which extends through the first water tank. The inlet tube is in fluid connection with the horizontal pipe extending horizontally above the water tank. The lower level leg pipe has an upper end connected to the end of the horizontal pipe and a lower end connected to a vacuum source. The vacuum source is used to initiate the flow of water through the siphon pipe. In addition, a quantity of air is injected into the siphon pipe so that more water flows into the siphon tube than flows out of the siphon tube. The extra volume of water in the siphon tube is diverted to and captured in the first tank. Similar siphon pipes are used to raise water to successively higher water tanks. At each level, the extra volume of water in the siphon pipe is captured in the water tanks. Pre-designated fluid levels are maintained in each of the water tanks.
Each of these prior art systems include complex valves and compressed air drive fluids to promote or sustain siphoning and siphoning flow rates. Compressed air systems are notoriously difficult to monitor and maintain. Pressurized lines and couplings tend to wear out or to leak and have to replaced often. To overcome the shortcomings of the prior art devices, a new and improved water lifting system based on siphoning which does not require the use of compressed air drive fluids is desired.
Accordingly, it is an object of the present invention to provide a new and improved apparatus for lifting water or other fluids based on siphons.
It is another object of the invention to provide a method and system for lifting water which further employs the raised water to generate highly efficient, clean and low cost hydroelectric energy,
In accordance with these and other objects, the present invention provides, in an embodiment, a new and improved apparatus and method for lifting water or other fluid from a first relatively lower position to a second relatively raised position. More particularly, the new and improved method of lifting a fluid from a relatively lower position to a second relatively raised position involves the steps of moving fluid in a generally upward direction stepwise from a lowermost tier to an uppermost tier in a plurality of stacked tiers. The fluid from the fluid source is initially upwardly siphoned to the lowermost tier. The fluid from the lower tier is then upwardly siphoned to a next adjacent higher tier.
The method of lifting water may include siphoning fluid from a fluid source to a receiving vessel in the lowermost tier. The fluid in the receiving vessel may be collected into a staging vessel. The fluid in the staging vessel may then be siphoned into a receiving vessel in an upper tier and then collected from the receiving vessel in the upper tier into a staging vessel in the same tier.
The method of lifting fluid may further include the step of initiating the siphoning of the fluid from the fluid source. The method may also include initiating siphoning of fluid into a receiving vessel in an upper tier from a staging vessel in a lower tier. The pressure in the receiving vessels may be slightly reduced for a selected period of time to initiate the siphoning flow. Alternatively, the receiving vessels and the staging vessels may be filled with fluid to desired starting fill levels.
A transfer conduit extending from a bottom of each receiving vessel to the bottom of each staging vessel in the same tier may be provided. The rate of flow of fluid from the receiving vessel into the staging vessel may be selectively variably controlled.
The method of lifting water may further include submerging the lower source end of the source siphon conduit in the fluid source and discharging the fluid from the fluid source into the receiving vessel in the lowermost tier via the source siphon conduit. The fluid entering the inlet opening of the source siphon conduit may be filtered.
The transfer siphon conduit may include an upper discharge opening and a lower inlet opening. The upper discharge opening may be positioned in fluid communication with the receiving vessel in the next upper tier and the lower inlet opening may be submerged in the fluid present in the staging vessel disposed in the next adjacent lower tier.
The liquid level in the receiving vessel and the liquid level in the staging vessel in the same tier may be maintained at a selected liquid level differential. The liquid level in the receiving vessel and in the staging vessel may be monitored.
The new and improved apparatus for lifting water from a relatively lower position to a second relatively raised position includes a plurality of tiers including a lowermost tier and at least one upper tier, a source siphon conduit and at least one transfer siphon conduit. Each tier includes a receiving vessel and a staging vessel. The receiving vessel is in fluid communication with a staging vessel. The source siphon conduit siphons fluid from a fluid source into the receiving vessel disposed in the lowermost tier. The transfer siphon conduit functions to siphon fluid into a receiving vessel in an upper tier from a staging vessel in the next adjacent lower tier.
The apparatus may include a means for commencing the siphoning flow through the source siphon conduit and the transfer siphon conduit. At least one vacuum or evacuation pump may used to initially slightly reduce the pressure in the receiving vessel for a selected period of time to initiate the flow through the siphon conduits.
A transfer conduit extending from the bottom end of the receiving vessel to the bottom end of the adjacent staging vessel may be used to provide the fluid connection between the vessels. A one-way flow valve may be provided in the transfer conduit to ensure that the fluid flows from the receiving vessel into the staging vessel. A means may be included to selectively variably control the rate of flow of fluid from the receiving vessel into the staging vessel.
The source siphon conduit and the transfer siphon conduit may each include a lifting leg portion and a relatively longer angled arm portion cantilevered from the lifting leg portion. The lifting leg portion may terminate in an inlet opening while the angled arm portion may terminate in a discharge opening. The inlet opening of the source siphon conduit may be submerged in the fluid source which the discharge opening may be placed in fluid communication with the receiving vessel in the lowermost tier. A filter may be used to filter the fluid entering the inlet opening of the source siphon conduit. The upper discharge opening of the transfer siphon conduit may be placed in fluid communication with the receiving vessel in an upper tier while the lower inlet opening may be submerged in the fluid present in the staging vessel in the next adjacent lower tier.
A means may be provided for filling the receiving vessels and the staging vessels to desired starting fill levels. Each of the receiving vessels and each of the staging vessels may be provided with a liquid level sensor for sensing the liquid level in each respective vessel. A controller may be used to maintain a selected liquid level differential between the liquid level in the receiving vessel and the liquid level in the staging vessel in each tier. The receiving vessels used may be airtight vessels.